It was once the largest fish seen and caught in the Songkhram River in Nakhon Phanom and surrounding areas. But recent years have yielded no sign of this majestic creature in the river basin, and many pinpoint fluctuating water levels in the Mekong as the reason for its disappearance.
Mekong River levels have dropped over the years, preventing the nutrient-rich water on which this giant fish species depends upon from flowing into the Songkhram River.
But the disappearance of the Mekong freshwater stingray prompts much larger questions: What does its absence signal for the people, ecosystems and biodiversity of the Songkhram River Basin, especially the lower part marked as Thailand’s 15th Ramsar Site? Who will be affected and how?
Phuthita Dokput and Kamol Sukin from GreenNews provide insights into species’ fight for survival in the second of a four-part Special Report titled “Songkhram [war] at the Songkhram River Basin”.
“Those Days with the Giant Fish”
“I remember the day a fish not so big, about two feet long and weighing about two kilos, was accidentally caught in a seine net in the Chaiyaburi estuary,” said Attaphol Nakham, 58, recounting his personal encounter with the giant Mekong stingray.
The species, which is known locally as “Fahlai”, has killed many men, said the retired fisherman from Nakhon Phanom’s Tha Uthen district.
“It avoids open, clear water and prefers to hide in deep, dark, muddy stretches. Its tail is hard and sharp like a big knife and can pierce through your back, believe me,” he added.
However, the fish is not that difficult to catch if you know how, said Wichit “Father Goh” Phongrat.
“The biggest one recorded is about 500kg, but I’ve only caught ones up to 20kg,” says the 71-year-old fishing veteran from Nakhon Phanom’s Sri Songkhram district.
The Mekong stingray can grow to 2 meters in length, almost matching the Mekong giant catfish. Wichit said they live most of their lives in the Mekong, only swimming up the Songkhram River to spawn before returning.
Attaphol recalled: “My father told me that one day while fishing, he suddenly felt something stuck to the bottom of the boat. He decided to dive into the water to investigate and saw a dark shadow that looked like a tree trunk as thick as his arm. He used his knife to free this thing and when it floated up, he saw that it wasn’t a tree but a freshwater stingray. It was so big, more than two meters long. He was shocked and swore he would never jump into the water like that again.”
He describes encountering a whole family of stingrays off the Mekong’s Don Kasek island, just above the Songkhram River’s mouth.
“They stayed close together. There were so many of them and they looked so scary.”
The mother was about a meter long while its offspring were about half that size, Atthapol recalled with excitement.
The Mekong species is similar to other stingrays, but the body is shaped like a pentagon with large eyes while the whip-like tail bears one or two poisonous spines that regenerate if broken. The upper surface of the body and tail is light brown in color, while a single row of thorn-like dermal denticles runs along the midline of the back. The underside of the body is white with a light yellow or orange streak.
The body of a fully grown Mekong stingray is about 40cm in diameter, though the largest specimen recorded was twice the size. The tail grows to 1.2 meters in length and can weigh more than 10kg.
The Mekong stingray (Dasyatis laosensis / Hemitrygon laosensis) feeds on invertebrates, small fish and various shellfish on the riverbed but occasionally floats up to the surface.
The size and unremarkable taste of its flesh are the first things that come to mind when locals think of this fish. But scientists like Dr. Chaiwut Krudphan, a lecturer at Ubon Ratchathani University’s fisheries department, view this giant as a crucial indicator of the river’s fertility.
“As a large fish, it needs well-circulating water and a proper diet, said Dr. Chaiwut, adding that the nutrient-rich soil brought by flooding feeds the diversity of food chains on which the Mekong stingray depends.
Do they still exist in the Songkhram River?
“I believe they do,” Attaphon said confidently. “But not as many as before. Many of them have been caught. Sometimes the babies are caught along with their parents.”
However, fellow veteran fisherman Wichit disagrees, insisting that the species is now extinct in the Songkhram River.
“Haven’t seen them for years. Usually, they come from the Mekong River. If there is a lot of water, you’ll find them. Every time you haul in the seine net [dragnet], you will find them. If the Songkhram River is flooded, they can swim into the area for spawning, but without floods there is no chance for the big fish to swim up here. If the
Songkhram and Mekong rivers don’t merge, there is no chance for the big fish to swim up here,” he said.
For the last three years, water levels have not been high enough for Mekong stingrays to spawn in the Songkhram,” he explained. “This kind of fish needs very deep, muddy water to spawn in.”
To Dr. Chawalit Wittayanon, a freshwater fish expert, it comes as no surprise that Mekong stingrays are disappearing from the Songkhram River.
“It’s not a common fish in the tributaries. They are usually found in the main Mekong River and will swim into the Songkhram River during floods to catch small fish and small aquatic animals for food. That’s why they are an excellent indicator of the river’s fertility. The greater the population of aquatic animals, the better the water quality and the higher the chance of seeing them.
A review of news reports about Mekong stingrays over the past 10 years confirms Dr. Chawalit’s words. Most reports highlighted the rareness and large size of stingrays caught in Thai and Lao provinces along the Mekong, while also noting that the rare fish were eagerly consumed.
“‘Fahlai’ caught in the Songkhram River is huge,” reads an August 3, 2009 headline at the Siamensis.org website. The report came with photographs and details of a 10-15kg Mekong freshwater stingray caught by villagers.
A June 17, 2013 report on a stingray in Thairath Online said: “Such a fish has not been caught in 50 years. The villagers helped cut the fish into pieces for sale at 100 baht per kilogram, so a variety of dishes could be enjoyed with their families. They believe it is good fortune to eat a rare fish like this.”
Krungthep Turakij newspaper reported on September 16, 2014: “The villagers were so excited to see a 200kg gigantic freshwater stingray appear on the Mekong River. It was caught and sold by fishermen and fell victim to human greed.”
A Post Today headline on November 5, 2015 screams: “Gigantic freshwater stingray caught for the first time in 20 years,” above the photograph of a giant stingray in perfect condition being dragged up to the riverbank with a rope.
“Astonishing! A 240kg gigantic ‘Fahlai’ was found in Nakhon Phanom. A villager said he had bought it from Lao people. It was cut into pieces for sale,” sanook.com reported on May 30, 2016, along with the image of a very large stingray on the back of a pickup truck.
Though these reports help confirm the species is not extinct, the bad news is that almost all specimens are being found in the Mekong mainstream. Research revealed only one report in the past few years, a Facebook post, of a giant stingray being caught at the mouth of the Songkhram.
“Photo of a freshwater stingray being caught in the Songkhram River estuary where it merges with the Mekong River in Chaiyaburi subdistrict, Tha Uthen district, Nakhon Phanom province,” read an October 28, 2020, post on the “Paknam Song Si Restaurant, Chaiburi” Facebook page.
Despite these reports, the International Union for Conservation of Nature (IUCN) has added the Mekong freshwater stingray to its Red List of Threatened Species.
‘Risk of extinction’ along with 642 other species
The Mekong freshwater stingray is one of the 20 species of fish in the Songkhram River that have been identified as “endangered”, reads a 2004 Thai Department of Fisheries’ report on the Songkhram River Basin.
However, many conservation experts believe that the actual number of endangered species is far larger, though no official research has been conducted to confirm this at present.
“There are at least 24 species missing,” said veteran fisherman Wichit, adding that many fish species he has known since he was seven have now disappeared.
Wichit recently contributed with other local fisherman to the “Thai Ban” research study to identify missing fish species.
“Apart from fish, there are approximately 642 species of flora and fauna in the area that are in the same situation,” said Yanyong Sricharoen, manager of the Lower Songkhram River Wetland Management Project. Yanyong is one of the people behind the registration of this wetland area as Thailand’s 15th Ramsar site.
Table: “642 species: biodiversity resources in the Lower Songkhram Basin today”
Implications of Survival
“The Songkhram River is so special. Though its watershed and length do not match the Mun and Chi rivers, Songkhram’s wetland area is important because it promotes aquatic ecosystems. This provides many opportunities to create suitable habitat including breeding and spawning grounds for aquatic animals,” said lecturer Chaiwut.
He said the Songkhram River Basin is dynamic, as the characteristics of its water resources change in line with the seasons, and this creates a variety of life in the freshwater ecosystem. These living creatures have adapted to the environment for generations, maybe thousands, even tens of thousands of years, he said.
“As a result, there are some species that can only be found in these specific areas.”
Dr. Chawalit, who has discovered at least 20 new fish species in Thailand and neighboring countries during biodiversity research since 1983, estimates there are approximately 200 species in the Songkhram wetland.
“Some 40 or 50 species are migratory fish such as the Siamese mud carp, silver barb, Pangasius and common sheatfish [Siluridae]. Some types of fish like snakehead, climbing perch and catfish prefer still waters. The diversity here is similar to that of the Mun River before it was blocked by dams. Now big fish rarely migrate there, so the dam-free Songkhram River is still in better condition,” he said.
Apart from its vast variety of fish and aquatic animal species, the lower Songkhram River Basin is also rich in vegetation. The riparian forest here forms the foundation of a rich and complex ecosystem. Some zones experience seasonal flows of water, while others are submerged all year round and exceptionally high in biodiversity.
“There are about 232 species of vegetation found in the riparian forest. Many are special as they are terrestrial plants that have gone through long evolution to survive in cyclical flooded ecosystems. We have rare and endangered plants that can only be found in the Northeast region,” reads a report on the value and importance of the lower Songkhram River wetlands prepared by WWF Thailand’s Department of Freshwater Resources Conservation.
This is in line with the Thai Ban study conducted by locals, which identified 208 species of plants and up to 28 ecological subsystems in this river basin. Plants and vegetation found here can be divided into seven categories – perennial plants, shrubs, climbing plants, vegetables, mushrooms, aquatic plants and grasses.
“The existence of these diversities has significantly contributed to both humans and natural ecology in the area,” Dr. Chawalit pointed out.
“People in the Sakon Nakhon Basin [as the area is also known] have been living off the river since prehistoric times. Biodiversity has certainly benefited local communities and given them food security. Of course, locals don’t consume all these 200 fish species, but the diversity needs to be conserved. Some small species are the food sources of 40 to 50 other species and some help the ecosystem thrive,” he said.
Riparian forests are the equivalent of coral reefs in the ocean – ‘medicine cabinets’ of health-giving herbs and antidotes. The Songkhram River Basin is carpeted with riparian plants, many of which are used as medicinal herbs by locals.
Diversity is also an important indicator of environmental degradation. For instance, heavy use of agricultural chemicals can kill off some fish species, acting as a warning sign for how locals should manage their ecosystem and environment.
“A large variety of fish species also helps diversify risks for the survival of fish or plants amid changing conditions,” Dr. Chawalit said.
Upcoming threats and their perceivable impact
“Fluctuating levels of the Mekong River plus development projects on the Songkhram River will likely be the key factors that threaten the survival of plant and animal species in the lower Songkhram Basin,” said Yanyong, who has spent years on conservation work in the area.
Veteran fisherman Wichit explained dams upstream had terminated the seasonal Mekong flood cycle.
“When the water level is too low, there are fewer fish. So there are not enough fish for everybody to catch. Because of the dams and the increasing population of people, fish are becoming scarce. The river level has also fallen because the Mekong is blocked with 11 dams right now,” he said, providing a locals’ perspective on the changing environment.
He added that modern fishing tools were also destroying stocks of fish, shrimp and mollusks.
“In the old days, we would only take fully grown fish and release the young ones. Now they kill everything they catch. Illegal fishing tools are used widely, and they fish all year round, even during the spawning season,” Wichit lamented.
Recent years has seen abnormal levels of water in the basin. In 2021, the area was only flooded for one month, in September. Unlike the previous year, the flood receded by October, leaving no fish behind.
Meanwhile, about 70% of the riparian forest has been transformed into off-season paddy fields, depriving fish of spawning grounds and nurseries and accelerating the depletion of stocks.
Disruption of the seasonal cycle also means locals are having to replace traditional foraged foods with agricultural products.
“We depend on the riparian forests daily, gathering bamboo shoots, mushrooms and other natural products,” said Wichit’s sister, who earns her living weaving mats. But she adds that the lack of floods this year has forced villagers to turn to vegetables, which are now in abundance.
In Dr. Chawalit’s view, dams are the biggest threat to the ecological balance of the basin.
“Big fish, especially types specific to this region, will be the first to disappear. The gigantic sawfish, also known as the carpenter shark, is already extinct [locally]. Not a single specimen was found in a recent expedition in Laos and Cambodia. The Mekong giant catfish has not been spotted in the Mekong River since the Xayaburi Dam started operating [in late October 2019],” Chawalit said. “When the Pak Mun Dam was constructed [in 1994], the impact was very obvious. From the 200 species of fish we saw in the past, only 40 to 50 species were left after the dam was built. Big fish are rarely seen. Fishermen in the Mekong River can only catch fish when the dam discharges water.”
Montri Chantarawong, a researcher with Mekong Butterfly, explained the biggest concern is the plummeting fish numbers in the Songkhram River. Despite claims to the contrary by authorities, the situation will get even worse if a dam is built on the river, he added.
Authorities say building a dam would bring more water, enabling fish to access the riparian forests and swamps and also feeding off-season rice crops,” Montri said
Exploring options for survival
If the Mekong stingray and other indicators of Songkhram Basin fertility are to survive, the biological resources must be managed properly. But the key questions are, how and by whom?
“Under the 2015 Fisheries Act, the provincial fisheries office has declared seven aquatic sanctuaries in the Songkhram River Basin. As a result, permission from the Fisheries Department must be granted each time you want to go fishing in these areas. This will help protect and preserve these aquatic species in the river,” Kamphon Loychuen, an official from the Nakhon Phanom Fisheries Office, said.
Nakhon Phanom governor Chatip Rujanaseri also acknowledged the need to consider environmental impacts before making development decisions.
He said this need was added to the government’s 20-year national strategic plan, and he would continue to respect them just as his predecessor as governor had done.
“The important thing is that development must go hand in hand with the opinions and participation of people in the community, so we can help each other manage the situation.”
Conservationist Yanyong, meanwhile, said transparency and cooperation with locals was crucial to every development project in the basin.
“First, we must adhere to the principle of free-flowing information.
Second, participation is important in each and every development project. Information must be open and shared with the community in a complete and comprehensive manner.”
Mekong Butterfly’s Montri added that the problem of depleted fish populations cannot be solved by dams and releasing fish.
“Fish stocks are low because the level of the Mekong River is not high enough to flow into its tributaries. So we have to find a way to bring the water back as close as possible to optimum levels. We must find a way to maintain a water channel between the swampland and the Songkhram River. The channel must be clear from blockages so fish can swim both ways and find more habitats,” he said.
Montri described fish releases as a mere ritual that is not effective in restoring stocks. “The Fisheries Department has also admitted this is not possible. You cannot breed all kinds of fish [for release].”
More scientific research is needed to understand how the Songkhram River ecosystems support local economies and how wide that support reaches, Dr. Chawalit said.
“We have a fair amount of knowledge, but we don’t have enough information and budget to study or examine the ecology or for long-term fishing.”
A study to collect data and statistics would be very useful for dam builders, enabling them to weigh up the pros and cons of going ahead with construction, he added.
“If the dam is built, you may only get water. If you don’t have dams and instead let the water flow naturally, will it be good for the community?”
Dr. Chawalit also pointed out that dam construction tends to yield quick economic benefits, but mainly for the contractor and those who need water in the industrial and agricultural sectors. State agencies also get a boost as these benefits were targets in their dam plans. But
such a narrow measure of success leaves out wider long-term environmental benefits.
“It is very important at this point to collect data on the diversity of resources in the Songkhram River Basin to build a bio-circular-green economy,” Dr. Chawalit said.
But local communities also have a vital role to play, according to veteran fisherman “Father Thong”.
“If the people in the Songkhram basin do not have a conscience, no solutions will work. It’s impossible for officials to sit and watch us all the time,” he said.
Fellow fisherman Wichit was optimistic. “If we let the river run freely and if Mekong River fish are still around, they will definitely come here to breed and spawn. If we really intend to preserve our ecosystem, we have to look at the whole picture because the Mekong and Songkhram rivers are connected as one.”
Biodiversity is crucial to the community’s livelihood and survival, he added. “It’s like a community kitchen… a supermarket. In the mushroom season, we eat mushrooms, in the bamboo shoot season, we eat bamboo shoots, in the insect season, we eat insects, and in the fish season, we eat fish. If we have a surplus, we can sell them.”
Aomboon Thipsuna, chair of the Northeast Community Network of the Mekong River Basin (ComNet Mekong), said local communities should be given the chance to discuss what should be kept to preserve their livelihoods. “They should not destroy natural resources, the environment or their own food sources. They need to make a decision together. Discussion and study are necessary to set up proper guidelines.”
Reporting for this story was supported by Internews’ Earth Journalism Network.